Can you solve the frog riddle? - Derek Abbott
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You’re stranded in a rainforest, and you’ve eaten a poisonous mushroom. To save your life, you need an antidote excreted by a certain species of frog. Unfortunately, only the female frog produces the antidote. The male and female look identical, but the male frog has a distinctive croak. Derek Abbott shows how to use conditional probability to make sure you lick the right frog and get out alive.
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Meet The Creators
- Educator Derek Abbott
- Script Editor Alex Gendler
- Director Outis
- Narrator Addison Anderson
by Brian Bors
Brian Bors
Lesson in progress
How to improve this video?
Yes. This video is incorrect. Chances of survival are always 100% or 0% (depending on the sex of the frogs). Calculating the chances of survival is therefore highly dependent on the amount of knowledge you have. "One frog croaked" gives you the knowledge "there cannot be two females" and ALSO gives you the knowledge "Either FM is wrong OR the possibility MF is wrong.". This second piece of knowledge is not taken into account. My suggestion for improving the riddle (and closer approaching the "boy or girl" paradox) is stating. "Female frogs of this species hate each other and will never sit next to each other" instead of talking about croaking. This makes sure FM, MF and MM have equal chances of being true based on the current knowledge.
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Yuan Zhang
Lesson in progress
Thanks for the idiographic insight:
a. The video is incorrect;
b. Chances of survival are either 100% or 0%;
c. Suggestion on improving the riddle.
a. At first, it is surprising to learn how enthusiastic people are to complicate things. If one of the two frogs croaked, then one of the two frogs is a male. The possibility of the remaining frog being a female is the same as the one sitting on the tree stump. Why take the male frog into account? Secondly, there are 12 other open discussions on the very same subject. Every other open discussion gets the spotlight, whereas no one admits it is all about the same subject!
b. The chance of survival doesn't equal to the possibility of the frog being female. Get it right, you'll live; get it wrong, you'll die. I thought I had 50% chance to survive.
c. Would life be simpler if the riddle states "Male frogs of this species hate each other and will never sit next to each other". This would increase my chance of survival to 100%.
Hugh O'Byrne
Hugh O'Byrne
Lesson in progress
While I'm not sure I agree with everything you write, I like the idea "Female frogs of this species hate each other and will never sit next to each other" - a lot. It makes for a good riddle, and, I think, perhaps a riddle closer to the one intended (I don't think the riddle asked is exactly what was intended).
